1. Field of the Invention
The invention relates to FIFO units used for buffering serial data.
2. Related Art
Usually in a serial communication application, a FIFO is used to buffer output data in case access to a data bus is lost. If access to the bus is lost in the middle of a transmission, the output data has to be re-sent from the FIFO when access to the data bus is regained. Normally, the FIFO therefore requires two pointers, an IN pointer and an OUT pointer. Each of these pointers requires circuitry to maintain it.
There has been a long-felt need for simplification of FIFO units. For instance, U.S. Pat. No. 5,732,011 illustrates a FIFO unit where the pointer unit is simplified. The patent speaks of creating a single pointer means, but the pointer means still needs to specify three pointers to operate the FIFO.